Good news from Alliant. They will be releasing a new powder called R16, sometime late Spring, early Summer. This powder will be similar in burn rate to H4350. While at SHOT show in Vegas all last week, I stopped by the Alliant booth and visited with them. This powder is part of their new temp stable powders, and was made to mock the burn rate of H4350. The interesting thing that Alliant mentioned was the lot to lot consistency of this powder. I have noticed (as well as other shooters) the lot to lot variation of H4350. This powder was stated to be more consistent from lot to lot. Also, the temp stability is greatly improved over H4350. I will be trying this new powder once it comes out.

I asked the same questions. R17 is a double base powder (as is most of the R series), and is an aggressive powder for the burn rate. The Alliant folks did admit that it was more temp sensitive in certain applications. The new R16 was engineered to be more temp stable than previous powders, with added coating and changes in the powder compounds.

When they say "consistent in all temps", I think they are referring to a ball powder. Ball/spherical powders are definitely more temp sensitive than extruded powders, since they have more surface area on the powder to be effected by the temps.

There's no way I would use R17 as a go to powder for year round shooting. When it first came out, I used it on a few loads, and the pressure swings from cooler to hot was dramatic. Near max load in Spring time, to blowing primers in the Summer time. R17 will get the speeds up, but with a big asterisk next to it.

I'm load testing with R17 for my 260 and the 120 gr Nosler BT. Looks like the chosen load will be about a grain under maximum. I would have preferred to do this in hot weather, but at a grain under max (if that's what I settle on) I expect to be Ok in hot weather. I guess we'll see. Accuracy looks really good so far. Of course, this is the rifle that you (Chad) had made up for me, and accuracy hasn't been bad with any load I've ever tried in it. The dang thing is a real shooter.

I'm working up a .30-06 load with 180 Partitions and Re17 the last week or so and am now trying to finalize seating depth. The velocity is insane, but I haven't fired that charge in temps above 40 F as of yet. If I end up going with it, I won't wait until we're having 90 degree temps to fire it again...I'll shoot it at 60 F to see if velocity climbs. I had an experience with Re17 a few years ago that gives me reason to be leary, but the truth is I don't KNOW what caused it. I won't let Re17 bite me!

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Originally Posted By: Ronald Reagan

It's not that liberals are not smart, it's just that so much of what they know isn't so.